Britons are broadly in favour of rewriting the genetic code of human embryos to prevent children from inheriting devastating diseases – but draw the line at designer babies and creating “cosmetic” organisms such as micro-pigs, fluorescent fish and perfect carrots.

The views were revealed in one of the first major surveys of public opinion on a new generation of genetic technologies that have given scientists the power to alter the DNA of living organisms with unprecedented ease and precision.

Commissioned by the Royal Society, the survey asked more than 2,000 people chosen to be representative of the UK population what they thought of various uses of genetic technologies as applied to plants, humans and other animals. More nuanced views came from small groups convened in Edinburgh, Norwich and London that explored the issues in greater depth.

The survey found more than three-quarters (76%) were in favour of correcting genetic diseases in human embryos once and for all, even though such DNA modifications are controversial because the tweaks – and any harmful side effects they may cause – would affect not only the patients, but their children and all future generations.

“That’s a very dramatic result,” said Robin Lovell-Badge, chair of the Royal Society’s genetic technologies programme and a leading scientist at the Francis Crick Institute in London. Scientists have shown in the lab that gene editing can mend faulty DNA in human embryos, but the procedure is not considered safe enough to create babies. In Britain the law prohibits gene-edited embryos from being implanted into women.

If the survey paints an accurate picture, and the British public are indeed comfortable with fixing defective genes in human embryos, it could encourage scientists to call for changes in UK law once the procedure is deemed safe enough to perform in humans. That may be easier to achieve after Brexit, Lovell-Badge said: “It might give us some opportunities to go a different way to other countries in Europe where the applications of these technologies to plants and animals and humans has been very restricted. It’s not a reason to leave Europe, but it may be one small silver lining.”

Sarah Chan, a bioethicist at Edinburgh University who worked on the survey, said no one would suggest a policy change on the back of a single survey, but that in principle she was in favour of editing human embryos to prevent serious diseases: “I’m of the view that if you can fix it once and for good, why wouldn’t you?”

The survey found even greater support for treatments that drew on gene editing to cure life-threatening disorders in children and adults, such as muscular dystrophy (83%), for which no effective therapies exist. Treatments for other diseases such as leukaemia, and less serious conditions such as arthritis, also gained widespread public approval, at 82% and 73% respectively.

The Royal Society commissioned the survey to explore the UK public’s views on the benefits and pitfalls the new genetic technologies will bring. “Genetic technologies have been advancing at breakneck speed,” Lovell-Badge told reporters at a briefing in London. “We need an inclusive discussion with the public on where we want these technologies to take us.”

Rapid advances in genetic science mean the entire six billion letters of a human’s genetic code can now be read in a few days for less than $1,000. With the advent of gene-editing tools, in particular an approach called Crispr-Cas9, it is now faster, cheaper and simpler to rewrite that DNA.

While gene editing has already paved the way for experimental cancer and HIV treatments and higher-yielding tomatoes and other crops, the technology raises fresh ethical issues. In the survey, people stressed the need for a global regulatory framework to ensure genetic technologies improved society and did not harm the environment or exacerbate inequality.

The survey found little enthusiasm for “designer” changes brought about by gene editing, with 69% opposed to edits to alter eye or hair colour, and 60% against modifications to boost abilities such as intelligence – a feat many researchers believe is far from possible today. As one person in the London focus group remarked: “If that technology is allowed, it would probably be accessible only to extremely rich people, and if they were allowed to use this technology, it would create an even bigger divide in society.”

It was not only designer humans that received a thumbs-down in the survey. While the public saw benefits in modifying mosquitoes to wipe out malaria, and in creating salmon that need less food to grow, only 19% thought genetic technologies would be put to good use making novel animals such as micro-pigs and fluorescent fish. Less than a quarter (23%) favoured better-looking fruit and vegetables.

“Simply making carrots look pretty, or animals look pretty, they didn’t really support,” Lovell-Badge said. “There has to be a sensible reason for the public to think this is an appropriate use of the technology.”